Change-speed transmission and control therefor



March 11, 1947. Q, H, BANNER 2,417,051v

CHANGE-SPEED TRANSMISSION AND CONTROL THEREFOR Filed Feb. 9, 1942 T0 LOW PRESJ URE J OUR CE Patented Mar. 11,V 1947 CHANGE-SPEED 'ramsmssroN AND coNfmoi. marron Oscar H. Banker, Evanston, lll., assigner, to New Products corporatie tion of Delaware n, Chicago, Ill., a com?? application Fermi-y 9, 1942, serial No. 42eme comm. (c1. 'i4-ases) This invention relates to a new change-speed transmission unit embodying a novel speed-responsve system in control of power train selection, rendering the unit particularly useful between the engine and propelling means of engine-driven vehicles, though not limiting the invention to such ileld. v

An important general object of the invention is the provision of an improved means responsive to functions in speed of both the drive and driven members in a change-speed transmission to determine whch power trains shall become opera-4 mediate and higher ratiov trains, speed responsive means operable when the transmission driven member attains a predetermined minimum speed, upon said shift execution. to close said common clutch, and speed-responsive means operable be- .Y

low a predetermined speed of the transmission drive member to cause operation of said disrupting means whereby the intermediate train is connected instead of the hizher ratio-train.

Still another obi ect is the provision of a changelspeed unitaccording to the next preceding ob-l tive when shift in trains or certain conditions precedent to a shift are executed.

Anoher object of the invention is the provision of a change-speed unit having a plurality of power trains selectively connectible in driving relation between drive and driven members by the disposition of a pair of clutches in various comrbinations with respect to their being opened or closed, there being speed-responsive means operable to cause closing of one of said clutches when the drive member exceeds a predetermined sneed and another speed-responsive means operable to cause closing of the other clutch when the driven member exceeds a predetermined speed.

Another object is the provision in a chansespeed transmission having overrunnlng power trains graduated in speed vratio and connectible in operative relation between drive and driven members by the synchronization and meshing of intermeshable members respectively pertain- Azu ing thereto upon decrease in the A"drive member speed relatively to that of the driven member in amounts corresponding to the dierence in the speed ratios of the trains between which a shift` predetermined driven member speed to enable the connection of an intermediate ratio train, and

:both of said speed responsive means being oper-y abe to enable connection of a higher ratio train only when both of said drive and driven members are rotating at or above their aforesaid predetermined speeds.

Another object is the provision in a changespeed unit having overrunning lower and intermediate ratio power trains from the lowerv of which a'shift is executable either into the intermediate train or into ahigher ratio train which includes disrupting means Operable to disrupt such train,` of a-clutch common to the interthe drive member drops to its ject and wherein said disrupting means for the higher ratio train is a clutch comprising part of the lower ratio train.

A further object is the provision of a changespeed unit operable with a'higher ratio power train between drive .and driven members while the higher ratio train and the subsequent open-f ing of a second clutch in the intermediate train. speed-responsive means for causing opening of the first clutch when the drive member drops below a predetermined speed. and an additional speed responsive means for causing opening of the second clutch when the driven shaft drops predeterminedly below the speed-of its operation when. during operation of the higher ratio train,

aforesaid predetermined speed.

These and other desirable objects inherent in and encompassed by the invention will be better understood from the ensuing description together with the annexed drawing showing a preferred embodiment. and wherein: 'x Fig. 1 is a side elevational view, partly in section, of a change-speed unit constructed according to the principles ofthe present invention; and

Fig. 2 is a chart illustrating the speed ranges in which the various power trains are establishable A and operable.

The transmission unit embodying a preferred form of the invention, shown in Fig. 1, comprises a drive shaft I0 jcurnalled within a bearing unit *Ii in the front wall I2 of a gear boxil, a coaxial driven shaft il Journalle'd within a bearing unit I5 `supported inthe rear wall Il of the gear box. 'I'he driven shaft il also has .a front en'd bearing portion'vll of reduced diameter piloted upon a set of needle` bearings l'within a bearing cavity I!" in the back end of the drive shaft. A coimtershaft' :p is suitably journalled upon a countershaft bearing rod 2| iixed atl its opposite ends in the front and back walls of the gear box.

The drive shaft l 6 is normally driven clockwise as viewed from the front or left end and the gearing associated with the transmission shifting is adapted to be connected between the drive and driven shafts in such diiferent combinations as t effect four forward drive power trains of different speed ratio in each of which the driven shaft I4 is rotated in the same direction as the drive shaft. Om.` reverse power train of speed reduction ratio is also establishable between the drive and driven shafts.

Hereafter the use of the terms "clockwise and counter-clockwise" will be with reference from a viewing point forwardly of the gearing. unless otherwise specified.

shifting a ring 22 of a jaw clutch 23 forwardly and to mesh its internal teeth 24 with the teeth 25 on the countershaft 26 while leaving portions of such teeth 24 meshed with teeth 26 on a sleeve 21 having a gear 28. integra1 therewith. The drive will then be from a drive shaft gear 29 through a ccuntershaft gear 36, an overrunning clutch unit 3l embodying clutch rollers 32 between a ring 33 and a clutch actuator member'34 of .any conventional structure, the countershaft 26, clutch 23, gear 28, a gear 35, an overrunning clutch unit 36 including clutch rollers 31 disposed betweenan inner peripheral portion of the gear 35 and a cluch actuator member 38 splined vat 39 to thedriven shaft I4.

The second speed power train is established by closing the rear jaw clutch 46 by the meshing of toothed counterparts 4i and 42 thereof which are respectively upon a gear 43 which is journalled upon the driven shaft i4 and upon a shifter ring 44 splined at 45 to the driven shaft. The clutch 46 is closed by shifting the ring 44 forwardly. In second speed the drive is from the gear 29 through gear 36, overrunning clutch 3l, countershaft 26. a gear 46 integral with the countershaft. said gear 43, clutch 40 and the shifter ring 44 tothe driven shaft. During operation of the second speed train the gears 46 and rotate the driven shaft and hence the clutch actuator member 38 at an overspeed with respect to the gear 35, as permitted by the clutch rollers 31.

Third speed is obtained by opening the clutch 46 and closing a. jaw clutch 41. This clutch includes a toothed ccunterpar1;48 upon the front end of the gear 43 and a toothed counterpart 49 upon a shifter ring 56 splined at 5| upon the back end of the drive shaft I6. This clutch is closed when the shifter ring 56 is slid backwardly, meshing the toothed counterparts 48 and 49. Power is transmitted from the drive shaft through the clutch 41. gears 43 and'46, clutch 23, gears 28 and 35. and the overrunning clutch 35 to the driven shaft. Meanwhile the gear 46 and the countershaft 26 will be rotated at greater speed than the gear 36 whereby the clutch 3| overruns.

Fourth sneed is incurred by closing both of the clutches 46 and 41, whereupon power will be transmitted from the drive shaft I6 through the cu+ch 41, the hub c-f gear 43, clutch 46 and the shifter ring 44 to the driven shaft, thed'iven shaft thus being driven at the same speed as the drive shaft. v

The reverse power train is established between the d rve and driven shafts by opening the clutch 23 and thereafter shifting a. reverse idler gear 52 rearwardly info mutual mesh with a reverse gear 53 rotatably fixed on the countershaft and a reverse gear 54 rotatablv fixed on the driven shaft. Any manual control means. as that .illllSl'lieQ in The first speed power train is established by my copending application Serial No. 357,388, filed September 19', 1940, for Automatic change-speed transmission, may be employed for shifting the clutch ring 22 and the reverse idler gear 52 in the manner Just described.

A shifter fork 55 having pins 5 5 in its depend-` `urges the same to rotate clockwise as viewed in Fig. 1 for closing the clutch 46. Such action of the spring 66 is obtained by having the end 6l Athereofhooked about one leg of the shifter fork and its opposite end 62 bearing reactively against a portion of the gear box. An arm 63 xed upon the journalled shaft 59 is connected by a link 64 with a vacuum motor' 65 controlled by a solenoid 66 which, when energized. actuates its core (not shown) for opening a valve 61 through which communication is then had by conduits 65 and 69 for operably connecting the motor 65 with a source of low pressure such as the intake manifold of a vehicle engine. The valve 61 may be of to the influence of the low pressure source by the the shifter fork 55 to open the clutch 46 or main-v tain the same open. A threaded stud 63h adthe general type shown' in e my Patent No.

2,171,534, excepting that it is operated by the' armature of the solenoid 66 instead of being manually operated.- When the motor 65 is subjected opening of the valve 61 upon energization of the solenoid 66, the link 64 will be lifted by the motor, causing counter-clockwise rotation of the arm 63, the shaft 59, a second arm, 63a, which is non-rotatively fixed upon said shaft, and hence justably-secured in the arm 63a abuts against the fork 55 to cause such rotation of the. latter 'against the force of the spring 66 during said counter-clockwise rotation of the cross shaft 59. Upon deenergization `of the-solenoid 66 the valve 61 terminates communication between' the conduits 68 and 69 and provides communication between the conduit 69 and the atmosphere whereby the motor 65 is deenergized to leave the clutch 46 subjected to the influence of the spring 66 which will then close the clutch 46 or place the end faces of the teeth upon the counterparts 4I and 42 in abutting relation according to whether these counterparts are synchronized and in the relative rotated relationfor meshing or not.`

Control of the clutch 41 is had by parts corresponding in every respect to those lust described with respect to the 'clutch 46 wherefore these parts are simply designated by the same respective reference characters with a prime added as an expedient to this description. It will be explained, however, that the spring 66' is wrapped about the hub of the shifter fork 55' in such a direction as to urge this shifter fork to rotate counter-clockwise as viewed in Fig. 1 instead of clockwise. wherefore said spring 66 biases the clutch 41 toward 'closed position. Although I prefer to employ relatively smallsolenoids 66 and 66' for controlling the motors 65 and 65' in manipulating the clutches 46 and 41, it should be understood that these solenoids could be designed to use their own power for operating .said clutches, in which event their armatures would be connected with the arms63 and 63' instead of with the valves 61 and 61.

Energization of the solenoid 65 is elected by 5 an electric circuit starting with ground indicated at 1I in the upper rilht-hand part` of Pig. 1 and including a conductor 12, an electric energy source 18, a conductor 14, contacts not shown but'operable to connect the conductor 14 with a conductor 15 whenia switch S, as the ignition switch for the engine of a motor vehiclefis closed.

conductor 15, the solenoid 54, a conductor 11, a normally closed governor actuated switch 18, conductor'18. and a normally closed manually opereine switch se back to ground tt el. The switch 18 has an operating stem 82 which when pressed upwardly opens contacts (not shown) for electrically connecting the conductors 11 and 18. A governor 88 havingv a shaft 84 driven from the drive shaft I through a worm pinion 85 is operable when 'registering speeds of the drive shaft above a predetermined minimum to move a plunger 86 against the switch operating stem 82 for opening the contacts, in the switch 18: and when the speed of the drive shaft drops below a predetermined minimum the plunger 88 willbe` retracted downwardly to permit closing of the switch contacts. 'While I here show the shaft 84 of the speed-responsive means driven directly from the transmission drive shaft i0, it will be understood that the shaft 84 may be driven from any engine-driven part. rotating as a function of the speed of said drive shaft.

A. circuit .for energizing the solenoid 58' also includes the conductor 15, said solenoid 85'. a

conductor 81 and a governor control switch 88 and a conductor 88 leading to ground at 80. The switch 88 is like the switch 18 and is driven by a governor unit 9i corresponding to the governor unit 83 but of which the operating shaft 52 is driven as a function of the transmission driven shaft Il through gearing as a worm pinion 88 fixed upon the shaft I4 and meshing with a worm gear portion 84 of the shaft 82. AThe switch 88 is also normally closed but openable by the gov-- ernor 9| when the driven shaft I4 exceeds a pre determined speed. y

When the present unit is installed upon a motor vehicle having engine ignition switch S, and

, 6 govcrnor|iisamimedtoactuatetocause opening ofthe switch 88 when the driven shaft reaches 750 R. P. M. and to "release" for causing said switch to open when the driven shaft drops to 300 R. P. M. It will be further assumed that at a vehicular speed of 10 M. P. H. the driven shaft rotates at 425 R. P. M. as does the drive shaft if the fourth speed train is connected. This condition is indicatedby the numerical notation 425m 'the fourth speed column ofthe chart and. opposite the 10 M. P. H. notations in the M. P. H. A columns at the right and left ends of thechart.

The speed ratios of the transmission power trains are assumed to be such that should the transmission be operating in first (while the vehicle -isdriven at 10 M. P. H.) the drive shaft rotateslat 1202 R. P. M.; thatvwith the second speed train in operation the drive shaft rotates at 882 R. P.' M.; and that with the third speed train inoperation the drive shaft rotates at 579 RJP. M. These speed notations 1202. 882 and 579 are shown in thechart respectively in the rst speed. second speed and third speed columns 'at the 10 M. P. H. elevation.. 'I'he chart also has corresponding R. P. M. notations in all four columns for vehicular speeds of 15, 20 and 25 M. P. H., as well as for other vehicular speeds referred more particularly hereinafter.

Assuming the first speed train to be in operation. the shift into second will involve closingl the rear jaw clutch wherefor a vehicular speed' must be attained at which the drive shaft goversuch switch is closed preparatory to operating the vehicle, each of the solenoids 58 and 55' will be energized for opening the clutches 48 and 41.

Solenoid. energizes beca-use ofthe connecting ofthe conductors 'I4 and 15 electrically together upon the closing of the switch S. the circuit continuing through the solenoid 58, conductor 11, the switch .18 which is then closed because the governor 83 is then driven at zero speed. conductor 19 and the normally closed manually operable switch 80 to ground completing the circuit. Since the driven shaft I4 is then at rest the governor 9| is quiescent, leaving the switch 88 closed wherefore the circuit for energizing the solenoid 5B is completed therethrough from A the conductor 15, the conductor 81, the switch 88 and conductorv 89 to ground at 88. I'he operator of the vehicle may then select whether the vehicle shall be'started forwardly or rearwardly by engagirg the clutch 28 or by sliding the reverse idler ear 52 into mesh with the reverse-gears '58 and 5 A typical operation of the present unit undercontrol of the speed responsive devices 83 andl 9| will be explained with reference to the chart in Fig. 2.

switch 18 when the drive shaft reaches 1000 R. P.. M. .and that it releases, to cause closing It wm be assumed the drive shaft' governor 83 actuates to cause opening of the' nor will be rotating at at least 900 R. P. M. when the engine slows down to synchronizing speed for making the 'second speed connection. This vehicular speed is found to be 10.08 M. P. H., so that while operating in first, say at l5 M. P. H..

when the drive shaft has exceeded its actuation" speed of 1000 R. P. M, for the governor and is still above the releasespeed of 900 R. P. M., the shift can be made into second for the solenoid 58 will be deenergized permitting the lspring 58 to place the clutch 40 in ratcheting relation pre-' paratory to meshing when the drive shaft slows down suiiiciently to synchronize the counterpart 4I with the counterpart 42. The speed range between limits of 10.08 M. P. H. and 17.6 M.'P. H. wherein a shift may be executed into second by momentary release of the accelerator pedal is termed the 15 M. P. H. range and illustrated graphicallyby the vertical band of arrows vpointing into the second speed chart column from the first speed column.

A shiftV from second to third involves opening the rear clutch 40 and closing the forward clutch 41, so that the vehicular speed range in which the shift is made into the third speed connecv tion will be such that the driven shaft governor will be "actuated and the drive shaft must slow down to such a speed in synchronizing the for ward clutch that the drive shaft governor will first release," closing theI switch 18 for energizing the solenoid IB-andthus causing the rear 'i clutch'to open. Actuation" of the driven shaft .governor at 750 R. P. M determines a vehicular speed limit that must be attained or exceeded before a shift can be made into third, although once this speed is reached the shift may be ex- ,ecuted at a vehicular speed as low as 7.06 M. P. H. at which the driven shaft governor releeses."

this corresponding to the aforesaid 30D-R. RAM.- of the driven shaft. 'The upper vehicular speedlimitfor .shlftingillto .third is 21.15 Mr P. H.-

above which the-' .drive shaftwould betwisting; i

suiliciently fast (above the release speed of 900 R. P. M.) when decelerated for causing closing of the clutch '41, to permit the clutch 40 to remain closed whereby fourth speed would be established instead of third. The entire speed range of 7.06 M. P. H. to 21.15 wherein a shift may be executed into third speed, following a vehicular speed of 17.6 M. P. H.,is graphically indicated by a vertical band of arrows, both long and short, pointing into the third speed chart column from its left edge. That part of this speed range indicated by the long arrows is the part normally used on a shift-up into third `and is termed the M. P. H. range since the4 round number 20 M. P. H. falls therein. The narrow or short arrow part of this speed designating band pertains to an operating range in which it is desired for the third speed train to remain connected should the vehicle be but temporarily decelerated.

A shift into fourth is possible any time above a vehicular speed of 21.15 M. P. H. say M. P. H., at which time both governors will be actuated and each clutch is synchronizable while the drive and driven shafts are rotating above ltheir governor releasing speeds of 900 R. P. M. and 300 R. P. M. The speed range extending up from 21.15 M. P. H. is termed the 25 M. P. H. range since such value falls within the range and is thought to be the round number mean oiA speeds at which shifts into fourth will be executed.

While operating in fourth, a shift down into third will automatically occur at 21.15 M. P. H. at which time the drive shaft governor 83 will release, it then registering a. drive shaft speed of 900, whereupon the switch 18 is closed and the solenoid 68 energized for causing opening of the clutch 40. Further decrease in vehicular speed will not cause disestablishment of the third speed connection until 7.06 M. P. H. is reached when the driven shaft reaches 300 R. P. M. causing release of the driven shaft governor and consequent opening of the forward clutch 41. Acceleration of the drive shaft would then result in the transmissionof power through the first speed train, both clutches 40 and I1 then beingopen.

There may be vtimes while operating the transmission unit in the second or fourth speed power trains when it is desirable that releasing of the drive shaft governor 83 shall not cause energization of the solenoid 66 and-the consequent disengagement of the rear clutch 40 for disrupting the power train then in operation. In other words, referring to the second speed and fourth speed columns in the chart of` Fig. 2, it might be desired to hold the second speed train in operation at vehicular speeds of less than 10.08 M. P. H. and likewise to hold the fourth speed train in operation below vehicular speeds of 21.15 M. P. H. Such control of the transmission unit is made possible by virtue of 91. When the switch 98 is closed by pressing inwardly upon an operating button 98 a circuit will be closed from the ungrounded side of the electric energy source 13 through the conductor 14, switch contacts controlled with the ignition switch S, conductors 15 and 1 8, solenoid 88, conductor 11, and said switch 98 to ground. Closing of the kick-down" switch 96 therefore causes energization of the solenoid 88 and the consequent opening of the clutch 40. Should the transmission unit be operating in the fourth speed connection at the time of operating the kickdown switch the shift will be into third speed, and should the transmission unit be operating in the second speed connection at the time of such operation of the kick-down" switch the shift will be downwardly into the rst speed connection.

A manually operated "kick-down switch, |80, similar to the switch 98 is connected between the conductor 81 and ground at IUI. This switch is also normally open, but when closed it is operable to cause energization of the solenoid 86' .and

consequent opening of the clutch 41 to immediately establish second speed from fourth or first speed from third.

The operation of the herein illustrated embodiment of the invention has been explained with the assumption of particular speed transmission ratio for the respective power trains and particular actuating and release" speeds for the governors 83 and 9|. .tions particular operating characteristics are attained that are shown graphically in Fig. 2 and which have been described with reference to that gure. It is contemplated, however, that changes may be made in the arrangement of power trains and in their speed ratios and also in the "actuating and "release'.' speeds of the governors.

While I have' herein shown and described a preferred embodiment with the view of fully illusthe manually operable switch 80 which, when the operating button B thereof is pressed, breaks the energization circuit for the solenoid 66 independently of the governor actuated switch 18.

The switch 8u may be placed in convenientreach of a vehicle operators foot upon the floor board nected between the conductor 11 and ground at trating the invention, it should be understood that the invention extends to other forms, ar-

rangements, structures, and details falling within the scope and spirit thereof and not sacricing all of its material advantages.

I claim:

1. In a change-speed transmission having a plurality of power trains of different speed transmitting ratio and a pair of clutches operable in different combinations with respect to their being opened or closed to determine which ofsaid power trains is connected in driving relation between drive and driven members said clutches being of the synchronise jaw type including drive and driven jaw components meshable to close their clutch upon deceleration of the drive component thereof to synchronism with the driven component thereof, the combination of clutch actuating means conditionable to become operable for closing one of said clutches upon its components attaining synchronism, a second clutch actuating means conditionable to become operable for closing the other of said clutches upon its components attaining synchronism, speed-responsive means operable according to the. speed of the drive member for so conditioning one of the clutch actuating means, and speed-responsive means normally continuously operable according .to the speed of the driven member for initially lso conditioning the other clutch actuating means at driven shaft speeds only in excess of those attained when connected with the drive shaft through lower of such speed connections while the drive shaft speed responsive means be- With these specific assumpi 9 comes operable to condition its associated clutch actuating means. Y V

2. In a change-speed having power trains of-relatively lower. intermediate and higher speeds. connectible between drive and driven members incident to incurring relatively raster, intermediate and slower speed V.of 'the drive member with respect to the driven member while power is transmitted thereby between said members, afirst clutch necessarily engaged for the establishment ofthe higher speed train, and a second clutch engageable to so'establish said higher speed'train incident to a shift-up from i the lower speed" train while the first clutch is engaged or to establish the intermediate speed train when engaged while the first clutch is disengaged; the combination of drive member speedresponsive means operable as a function of the drive member speed, driven member speed-re-V sponsive means operable 'as a function of the driven .member speed', clutch actuating means under control of the driven member speed-responsive means and operable in the execution of a shift-up from the lower ratio train. iwhen suclr speed-responsive means registers driven member speeds above a predetermined minimumo cause engagement'of the second clutch, and clutch actuating means under control of the drive memand consequentfestablishment of the intermediate ratio train instead of the higher ratio train in the execution of said shift-up.

3. In a change-speed transmission havingpower trains of relatively lower, intermediate and higher speeds connectible between drive and driven members incident toincurring relatively faster, intermediate and slower speed of the drive member with respect to the driven member while power is transmitted thereby between said members, and a`clutch common to the intermediate and higher speed trains in the respect that it is transmitive of force ineach of such trains, said clutch including drive and driven components respectively rotatable according to the speeds of the drive and driven members and meshable when synchronized to mobilize the higher speed train providing the latter is not disrupted or to mobilize the intermediate train Ishould the higher speed train be disrupted; the combination of drive member speed-responsive means operable as a' function of the drive member speed. driven member speed-responsive means operable as a function of the driven member speed, means operable incident to the execution of a shift-up the driven-member speed-responsive means registers speeds in excess of a predetermined minimum and upon deceleration of the drive member to synchronize the clutch components, and means f operable moment to suon smit-up and under con.v trol of the-*drive member speed-responsive means to cause disruption Iof the higher speed train and v consequential establishment of the intermediate ponents should the driven member speed be so low that the drive member falls below a predetermined in eifecting said lsynchronism of the clutch components.

'4. In a change-speed transmission having relatively lower and intermediate overrunning speed transmission power trains operable between drive and driven'members and from the lower of which trains a shift-up is executable either into the intermediate speed train or into a higher speed train by bringing about deceleration of the drive member relatively to the driven member; the

combination or power trein disrupting means operable to disrupt the higher speed train, a clutch common to the intermediate and higher speed trains in the respect that it is transmitive of force in each of such trains. said clutch including drive and driven .components respectively rotatable as functions of the drive and driven member speeds during operation of the lower speed' train and meshable when synchronized to Aoperably connectthe higher speed train between said members when the latter power train is not disrupted by said disrupting means and to operably connect the intermediate speed -train between said members when the higherspeed train is so disrupted, drive member speed-responsive means.

driven member speed-responsive means, meshing means for said clutch, said driven member speed-responsive means being in control of said clutch meshing means and being operable when the driven member attains a speed suitable for,

connection of the intermediate speed train to effect meshing of said clutch counterparts upon their synchronization brought about by decel-v eration of the drive member, the drive member speed-responsive means being in control of said power train disrupting means and being operable to cause operation of said disrupting means when said drive member, in synchronizing said clutch components, decelerates to a speed below which it is undesired to employ the higher speed train between said drive and driven members.

5. In a change-speedtransmission having relatively lower and intermediate overrunning speed 'ton power trains operable between drive and driven members and from the lower of which trains a shift-up is executable either vinto the 4intermediate speed train or into a higher speed to become vclosed when synchronized, a second clutch common to said intermediate and higher ratio trains in the respect'that it is transmitive of force in each of such trains, said second clutch including drive and driven components 'respectively rotatable as functions of the drive and driven member speeds duringvoperation of said lower speed train and meshable when synchro` nized to close and thus operably connect the higher speed train between said members when the. nrst clutch is closed or to operably connect the intermediate lspeed train between said mem-,- bers when the nrst clutch is open, clutch actuating means operable to mesh and demesh said clutches. drive member speed-responsive means speed train by the meshing of said clutch cpm- 75 operableto cause actuation of said clutch oper- 11 ating means, when the driven member is rotating at a speed suitable for connection oi the lower speed train, to close the irst clutch upon synchronization of its co/unterparts brought about by deceleration of the drive member, driven member speed-responsive means operable to cause actuation of said clutch operating means, when the driven member exceeds a predetermineg greater speed, to close the second clutch upc synchronization of its counterparts brought about by deceleration of the drive member, such closing o1 the second clutch effecting establishment ot the higher speed trainl when the nrst clutch ren'ains closed, but the drive shaft speedresponsive means being operable to cause actuation of said clutch operating means for opening the rst clutch prior to closing of 'the second clutch and consequent establishment of the in termediate speed train by said closing of the second clutch should such greater speed of the driven member be so low that the drive member falls below a predetermined speed in effecting said synchronism oi the second clutch counterparts.

6. In a change-speed transmission, drive and driven members, relatively higher and `lower speed power trains drivably connectible between said members and of which trains each includes a disrupting means operable to disrupt the same, the lower speed train being overrunning to remain mobilized preparatory to becoming drivingly connected upon disruption of the higher speed train, means operable according to the drive member speed to operate the higher speed 12 train disrupting means during operation of suc train when the drive member drops below a predetermined speed. and means operable according to the driven member speed to operate the lower speed train disrupting means during operation of such trainv when the driven shaft drops predeterminedly below .the speed at which it' would be driven during operation of the higher speed train at the instant o! its disruption by the aforesaid operation of the means operable according to the drive member speed.

. OSCAR H. BANKER.

REFERENCES CITED The following references are of record in the file of this patent:

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